Apparatus foe making exteacts feom tan bark



(N Mod 1.),

0 G .J. 8v W. N; HUTCHINGS;

APPARATUS FOR MAKING EXTRAUTS FROM TAN BARK. No. 444,068.

Patented 11111.76, 1891.

\PS/Eessas Um S M time TATES ATENT rrrcn.

JOHN HUTCHIN GS AND VVILLIAH N. HUTOHINGS, OF WVARRINGTON, ENGLAND.

APPARATUS FOR MAKING EXTRACTS FROM TAN-BARK.

SPECIFICATION forming part of Letters Patent No. 444,068, dated January 6, 1891.

Application filed May 20,1890. $erial No. 352,481. (No model.)

To all whom it may concern:

Be it known that we, JOHN HUTOHINGS and WILLIAM NELsoN HUTCHINGS, subjects of the Queen of Great Britain, residing at lVarrington, in the county of Lancaster, in the Kingdom of England, have invented certain new and useful Improvements in Tanning, of which the following is a specification.

This invention has for its object an easy, thorough, and expeditious mode of causing the liquor to circulate in tan-pits for the purpose of extracting the soluble ingredients of tanning material or of bringing the liquor to act with greater effect on the hides. At present in extracting the soluble ingredients the material is thrown into a tan pit or leach and then water or liquor added. The stuff swells up considerably and becomes an almost impermeable mass, requiring a very long time for the extraction of the tannin. Now,

by our experiments we find that, first, the mass must be considerably subdivided to enable the water or liquor to pass through it readily and extract the contents easily, and, second, gentle agitation and circulation greatly con.- tribute thereto. To effect this object we have found that it is best to separate the tanning material by pervious partitions only part filled and with sufficient space in each to permit the full expansion of the material caused by absorption, and thereby avoid consolidation and circulate the liquor continuously through these. To carry this out in a simple manner and with nominal power, we have designed the following arrangement, illustrated in the drawings hereunto appended, from actual apparatus in use by us, in which- Figure 1 is a vertical section of the apparatus, and Fig. 2 a plan. Fig. 3 is detail.

In the drawings, A is an ordinary tan pit or leach of any convenient sizesay ten feet square and six feet deep; B B, baskets, also of any convenient size. The ones We use in pits of the dimensions set forth are two feet square (outside extreme dimensions) and about eleven inches deep.

0 is a square wooden trunk of boards two inches thick, inclosing a plunger D. This is a simple strong box of wood fitting'the trunk and about three feet deep, partially filled with stones or other weighty matter and having a simple pump-clack d at bottom. A block of stone, &c., having on the top a square piece of leather fitting the tube, which acts as a single pump-clack, will do equally well.

E is a rope or chain on which plunger D is suspended. This passes over pulleys F to a rocking beam G, which actuates not merely this one plunger, but all the others in the tan-yard by means of ropes. Beam G oscillates on center H and is rocked by pinI on revolving wheel J. The latter revolves about, say, ten to twenty times a minute. About thirteen for general purposes is found to give the best results.

K are channels hereinafter described; L, steadying-boards holding the trunks securely in place and forming supports for planks M to walk upon.

An overhead shaft with cams keyed on, one for each plunger, may in some cases be more convenient. It has the advantage of distributing the work to be done in the course of a revolution of the shaft. For hand-working, a simple crank-handle and Winch can be used.

The baskets E are of any ordinary structure. W'e prefer split half-inch cane with a skeleton or ribs of slightly thicker whole cane, as shown in Fig. 3. The upper and lower rims of these baskets are about the same width and are a moderately good fit, so that the liquor rises or falls through them, being unable to pass between them easily and in quantity. i

The mode of using is as follows: The baskets, about half filled with the bark valonia or other tanning material, are piled one upon the other, filling the pit, except the irregularly-shaped bottom, in which channels K lead from the center in a star-like form or otherwise under the baskets. The pit being nearly filled with baskets, liquor is pumped in till it is nearly full. The plunger is set going, alternately sinking to the bottom and rising to a point a little above the surface of the liquor. As it descends, the clack opens and lets the liquor through, or, if the plunger be filled with stones, as we sometimes Work it, it forces the liquor out through the radiating or other channels under the baskets, through which it rises. As the plunger rises, the liquor is again sucked back to below the plunger and the liquor above the plunger has overllowed into the surrounding baskets. This pumping, or ebb and flow, goes on till the liquor in the pit has taken up all the strength from the material, which it is capable of doing, a weaker liquor being substituted at each re newal.

\Vhcn the apparatus is used for tanning hides, the baskets are removed and the hides hung vertically or placed horizontally in any convenient manner in the pit. If placed hori- /.ontally, the hides should be kept separated by layers of tanning material or otherwise. The pumping is then carried on as already described.

Ve claim as our invention- 1. The combination of the plunger D and the trunk O, with a series of surrounding superimposed pervious supports carrying layers of the tanning material to be exhausted, substantially as described.

2. The combination of the pumping device 0 D, with the baskets B B, superimposed and in layers, covering the area of the pit not occupied by the pumping device (1 .l), substantially as described.

3. lhe combination of the pumping device C D and channels K with superimposed layers of exhaustible tanning material, having spaces between the layers, substantially as described.

4. The combination, in a tan-pit, of a pumping device 0 D, the channels K, and a per- Vious supporting device above for the tanning material.

5. The combination of the pit A, trunk 0, supports L, and planks M, substantially as and for the purposes described.

6. The combination of the pumping device C D, line E, rocking beam G, and revolving eccentric-pin I, substantially as and for the purposes described.

In testimony whereof we have signed our names to this specification in the presence of two subscribing witnesses.

J. IIUTCIIINGS. \V. N. HUTCHINGS.

\Vitnesses:

AUBREY WHITE, WM. PARSONS. 

